Vehicle grilles are provided to direct airflow into the engine compartment of a vehicle when the vehicle is driven. Closing the vanes of the grille may also be advantageous, provided that adequate cooling airflow is provided to the engine compartment, to reduce aerodynamic drag and improve fuel economy. Under some conditions, such as when the ambient air and engine are cold, it may be advantageous to reduce airflow into the engine compartment to allow the engine to warm more quickly and provide warm air sooner through the heating and air conditioning system.
Active grille shutters are operated by an electric motor that drives a gear set. Snow and ice may build-up on movable vanes and impede operation of the active grille shutter and may become inoperable. Active grille shutters are most susceptible to freezing when in a fully closed state at or about freezing temperatures and when they are subjected to freezing rain or snow.
This disclosure is directed to addressing the above problems and other problems relating to the operation of an active grille shutter system.